May/June 2015 Issue
Addictions Advisor: Medication-Assisted Therapy for Opioid-Dependent Pregnant Women
Use of heroin and abuse of prescription opioid analgesic medications is a topic garnering increasing attention due to the widespread nature of the problem and the challenges of treating it. Those challenges are compounded in the case of pregnant women, and data from the 2010 National Survey on Drug Use and Health find that an estimated 4.4% of pregnant women reported some kind of illicit drug use in the past 30 days (U.S. Department of Health and Human Services, 2010). Standards of care for opioid-dependent pregnant women aim to address the comprehensive prenatal care needs for both mother and fetus.
In 2014, the American College of Obstetricians and Gynecologists (ACOG) reaffirmed its Committee Opinion, asserting that the current standard of care for pregnant women with opioid dependence should be referral for opioid-assisted therapy with methadone, adding that emerging evidence suggests that buprenorphine should also be considered (American College of Obstetricians and Gynecologists, 2014). The opinion cautions against medically supervised tapered doses of opioids during pregnancy because of the high rate of relapse, and warns that abrupt discontinuation of opioids can result in preterm labor, fetal distress, or fetal demise. It also notes that neonatal abstinence syndrome is an expected and treatable condition that follows prenatal exposure to opioid agonists.
The Effects of Opioids
Heroin and misused prescription opioids (i.e., "prescription painkillers," such as oxycodone, codeine, or morphine) produce a short-acting effect, meaning that the "high" wears off in four to six hours, prompting the initiation of withdrawal symptoms. Every time the mother goes through the withdrawal cycle, the fetus does too; it is these repeated episodes of withdrawal that are extremely damaging to the fetus. ACOG's Committee Opinion notes that during pregnancy, chronic untreated heroin use, and the resultant erratic disturbance to the uterine environment, is associated with an increased risk of fetal growth restriction, abruptio placentae, fetal death, preterm labor, and intrauterine passage of meconium (American College of Obstetricians and Gynecologists).
Given these risks, exposure to a steady dose of a medically supervised opioid medication is less damaging to the fetus than the effects of repeated withdrawal. Therefore, medication-assisted therapy (MAT) provided at an effective dose can prevent the onset of withdrawal, as well as eliminate drug cravings and block the euphoric effects of other narcotics, according to Kaltenbach.
Kaltenbach noted that an "effective dose" is critical, because a dose that is too low may prevent onset of withdrawal but may not eliminate drug cravings or block euphoric effects of other narcotics. In that case, the woman may continue to use illicit substances in addition to MAT, thus increasing risk to the fetus (Kaltenbach & Otero).
Neonatal abstinence syndrome (NAS) is defined as the syndrome of problems that occurs in a newborn exposed to opioid drugs while in utero. This is an expected and treatable condition that follows exposure. Kaltenbach emphasized that babies are not born "addicted" to opioids. She stated, "Addiction is a psychiatric diagnosis which requires other criteria in addition to physical dependence. Babies have passive physical dependence to a drug which has crossed the placenta which can be treated." She added that all babies exposed undergo withdrawal, but the severity and need for pharmacological intervention varies greatly (Kaltenbach & Otero).
ACOG's report notes that limited data exist on long-term effects of fetal opioid exposure, however, "for the most part, earlier studies have not found significant differences in cognitive development between children up to 5 years of age exposed to methadone in utero and control groups matched for age, race, and socioeconomic status, although scores were often lower in both groups compared to population data" (American College of Obstetricians and Gynecologists, p. 5).
The Functions of Opioid Agonists Therapies
Two pharmacological options exist for MAT: methadone and buprenorphine.
Buprenorphine was approved in 2002 and is delivered in two formulations, marketed as Subutex and Suboxone. Suboxone contains buprenorphine as well as naloxone which is an antagonist added in order to control for diversion. However, there are not sufficient data on the effects of naloxone on fetal development, so Subutex (which contains only buprenorphine) is recommended for pregnant women.
Buprenorphine is classified as a Schedule III drug, and, as allowed by the Drug Treatment Act of 2000, can be prescribed for opiate addiction treatment by specially qualified doctors in private offices. This allowance was intended to increase access to treatment.
The class of prescription benzodiazepines and misuse of these medications presents a difficult problem. Benzodiazepines are frequently prescribed to women for anxiety disorders, and include medications such as alprazolam (Xanax), clonazepam (Klonapin), lorazepam (Ativan), or diazepam (Valium). All classes of benzodiazepines cross the placenta and make NAS more complex and prolonged, and some are more dangerous than others. Some are classified as Class D, meaning that the benefits may outweigh the risks, while others carry the Category X rating, meaning that the risks clearly outweigh any benefits.
Data on abuse of benzodiazapines are difficult to ascertain, though Kaltenbach provided anecdotal perspective on the prevalence in her lecture, "Benzodiazepines and the Pregnant Patient: Special Challenges," delivered in 2012 at a conference on the management of benzodiazepines in medication-assisted treatment sponsored by SAMHSA and other stakeholders in Philadelphia (Kaltenbach, 2012).
In preparation for a rigorous clinical trial on methadone and buprenorphine in pregnant women, 199 women were screened for eligibility. Forty-four percent of women at screening were ineligible for study because of a benzodiazepine substance use disorder.
Because the high comorbidity of anxiety disorders and substance use disorders, careful assessment of both prescribed and illicitly obtained medications is crucial. Polysubstance abuse in pregnant women presents very complex medical issues and requires interdisciplinary treatment models that address the myriad issues presented.
Screening for Substance Use
• Parents: Did any of your parents have a problem with alcohol or other drug abuse?
• Partner: Does your partner have a problem with alcohol or drug abuse?
• Past: In the past, have you had difficulties in your life because of alcohol or other drugs, including prescription medications?
• Present: In the past month, have you drunk any alcohol or used other drugs?
— Liza Greville, MA, LCSW, is in full-time clinical practice in rural Pennsylvania and a contributor to Social Work Today.
Kaltenbach, K. (2012, October 29). Benzodiazepines and the pregnant patient: Special challenges. [Archived video presentation]. Retrieved from https://www.youtube.com/watch?v=sAxsK1j3a5U.
Kaltenbach, K., & Otero, C. (2011, August 4). Medication assisted treatment during pregnancy, postnatal and beyond. [Archived video presentation]. Retrieved from http://www.cffutures.org/presentations/webinars/medication-assisted-treatment-during-pregnancy-postnatal-and-beyond.
U.S. Department of Health and Human Services, Substance Abuse and Mental Health Services Administration, Center for Behavioral Health Statistics and Quality. (2010). Results from the 2010 national survey on drug use and health: Summary of national findings. Retrieved from http://www.samhsa.gov/data/NSDUH/2k10NSDUH/2k10Results.pdf.